The present invention relates to a resealable label flap positionable to cover an opening in a product package containing removable articles such that the label flap can be repeatedly removed and reapplied to access the articles contained within the package. More specifically, the present invention relates to a multi-layer, resealable label flap that includes an label stop that inhibits the complete removal of the label flap from the product package.
Resealable label flaps are commonly used with product packages that include packaged sheet-like removable articles that have been thoroughly wetted with a liquid prior to packaging. The product package is generally constructed from a thin, liquid-impervious material that has an opening over which the label flap is removably adhered. Typically, the label flap is a strip of flexible or semi-rigid thermoplastic material having a removable pressure-sensitive adhesive applied to one surface of the label. The removable adhesive creates a generally air-tight seal around the package opening to prevent the packaged removable articles from drying out during storage.
Typically, resealable label flaps include one end that is more securely attached to the product package to create a "stop point" that prevents the user from completely removing the label flap from the product package. If the label flap is completely removed, the flap may be incorrectly repositioned back on the product package or may be completely lost by the user. If the label flap is incorrectly repositioned or not reapplied, the wetted removable articles contained within the product package are vulnerable to contamination and may eventually dry out, thus reducing the product's effective life.
In the field of resealable label flaps, there are several methods currently used to affix the label flap to the package body to create a stop point that inhibits the complete removal of the label flap from the package. One method, as embodied in U.S. Pat. No. 4,552,269 to Chang and U.S. Pat. No. 5,725,311 to Ponsi et al., includes the procedure of die-cutting the label flap so that upon opening, the label flap will hinge between the die-cuts and remain adhered to the package. The die-cuts create a stop point that inhibits the complete removal of the label flap from the product package. Although this method has proven effective to prevent complete removal of the label flap, the additional required step of die-cutting the label increases the complexity of the production process and requires additional equipment.
Another method used to create a stop point for the label flap is shown and described in U.S. Pat. No. 4,840,270 to Caputo et al. This method involves treating a specific area of the package body's surface with a corona discharge so that the adhesion characteristics of a treated area are improved. After the application of the pressure-sensitive label flap, the label flap can be pealed easily up to the corona-treated zone. At the corona-treated zone, the adhesion between the label flap and the package body is substantially greater, which prevents the inadvertent complete removal of the label flap from the package during opening. Although this type of method prevents the label flap from being completely removed from the product packaging, the process of corona treating the product package in a specific area increases the time required to form the package and increases the cost to produce the product package including the label flap.
Another method for creating a stop point for the label flap is described in U.S. Pat. No. 5,035,518 to McClintock. In forming a label flap using this method, two types of adhesives are applied to the back of the label. A first, resealable adhesive is applied to a substantial portion of the label, while a second, permanent adhesive is applied to a narrow strip of the label. The permanent adhesive applied to the small strip of the label creates a substantial bond with the product package to prevent the label flap from being completely removed from the product package. This method of forming a label stop suffers from several drawbacks. For example, the application of two types of adhesive material to a single label is difficult to control and the two adhesives must be of the same family, since the application equipment used to apply the adhesives is typically the same.
Therefore, it is an object of the present invention to provide a resealable label flap that includes an label stop that securely retains the label flap on the product package to prevent the label flap from being completely removed from the product packaging. It is an additional object of the invention to provide a resealable label flap that is easy to manufacture using conventional label forming machinery. It is a further object of the invention to provide a multi-layer label flap that incorporates both a permanent adhesive and a resealable adhesive to allow the label flap to be resealably attached to the product packaging while preventing complete removal of the label flap from the product packaging.